| 摘要 |
PROBLEM TO BE SOLVED: To provide a fly ash circulation type exhaust gas treatment method capable of stably reducing the concentration of acid gas of a bag filter outlet up to a low level in the blowing-in equivalent ratio of a little sodium-based chemical, by further effectively using an unreacted portion unreacted with the acid gas, by almost completely converting the sodium-based chemical such as sodium bicarbonate introduced into an exhaust gas flue into sodium carbonate, in the exhaust gas treatment method for removing the acid gas such as hydrogen chloride and sulfur oxide included in exhaust gas.SOLUTION: The fly ash circulation type exhaust gas treatment method returns a part of this bag filter fly ash to the exhaust gas flue 1 on the bag filter inlet side, by taking out the fly ash (smoke dust in the exhaust gas + the sodium-based chemical and a reacted product material of the acid gas + an unreacted sodium-based chemical) collected by a bag filter 2 from a bottom part 11 of the bag filter. A circulation amount of the bag filter fly ash is set to 3 times - 14 times expressed by the fly ash circulation magnification ratio. |
